def approximateOrbit(object1, object2, epoch):
if object2.epoch == object1.epoch:
proportion = 0
else:
proportion = (epoch - object1.epoch) / (object2.epoch - object1.epoch)
if (0.95 < object1.ecc and object1.ecc < 1.05) or (
0.95 < object2.ecc and
object2.ecc < 1.05) or (object1.isElliptic != object2.isElliptic):
state1 = object1.getStateByEpoch(epoch)
state2 = object2.getStateByEpoch(epoch)
return kepler.createOrbitByState(
kepler.StateVector(
kepler.Vector3(
approximateNumber(state1.position.x, state2.position.x,
proportion),
approximateNumber(state1.position.y, state2.position.y,
proportion),
approximateNumber(state1.position.z, state2.position.z,
proportion)),
kepler.Vector3(
approximateNumber(state1.velocity.x, state2.velocity.x,
proportion),
approximateNumber(state1.velocity.y, state2.velocity.y,
proportion),
approximateNumber(state1.velocity.z, state2.velocity.z,
proportion))), object2.mu, epoch)
if object1.isElliptic:
ma = approximateAngle(object1.getMeanAnomalyByEpoch(epoch),
object2.getMeanAnomalyByEpoch(epoch), proportion)
else:
ma = approximateNumber(object1.getMeanAnomalyByEpoch(epoch),
object2.getMeanAnomalyByEpoch(epoch),
proportion)
if approximateNumber(object1.ecc, object2.ecc, proportion) < 0:
print(object1.epoch, object2.epoch, epoch, proportion)
print(approximateNumber(object1.ecc, object2.ecc, proportion))
print(object1)
print(object2)
return kepler.Orbit(
approximateNumber(object1.ecc, object2.ecc, proportion),
approximateNumber(object1.sma, object2.sma, proportion),
approximateAngle(object1.aop, object2.aop, proportion),
approximateAngle(object1.inc, object2.inc, proportion),
approximateAngle(
object1.loan +
object1.getNodalPrecessionByEpoch(EARTH_R, EARTH_J2, epoch),
object2.loan +
object2.getNodalPrecessionByEpoch(EARTH_R, EARTH_J2, epoch),
proportion), ma, epoch,
approximateNumber(object1.mu, object2.mu, proportion), False)
def createOrbit(tle):
date = datetime.datetime(
tle['epoch_year'], 1, 1, 0, 0, 0, 0,
tzinfo=TZ()) + datetime.timedelta(tle['epoch_time'] - 1)
epoch = (date - datetime.datetime(2000, 1, 1, 12, 0, 0, 0,
tzinfo=TZ())).total_seconds()
meanMotion = tle['mean_motion'] / 86400
sma = (EARTH_MU / (2 * math.pi * meanMotion)**2)**(1 / 3)
return kepler.Orbit(tle['ecc'], sma, deg2rad(tle['aop']),
deg2rad(tle['inc']), deg2rad(tle['raan']),
deg2rad(tle['ma']), epoch, EARTH_MU, False)